A defense that was playing without its leader, Sean Lee, got exposed as the game went on, giving up scoring drives on five straight possessions in the second half.

For the first time since Week 3 last season, the Cowboys’ offense scored on its first four possessions, giving Dallas a 24-16 halftime lead, but then the offense went stagnant. It ran 16 plays on its first four possessions of the second half and picked up just two first downs. The Rams turned that deficit into an eight-point lead.

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The end result was a defense that was worn out. Todd Gurley became the second running back in three games to rush for more than 100 yards against Dallas. Jared Goff was sacked just once. And the Rams did to the Cowboys what the Cowboys want to do to their opponents: grind the clock to bits.

"The margin is so small in this league," tight end Jason Witten said. "You have leads like that, you've got a chance to put them away and we couldn't do it."

A number of plays stand out:

Two Cowboys’ special-teams miscues led to 10 Los Angeles points. Ryan Switzer’s fumbled punt changed the tenor of the game in the second quarter, with the Rams answering with a touchdown that cut the Dallas lead to 17-13. A 66-yard kickoff return led to a Rams field goal earlier.

On the first play of the second half, DeMarcus Lawrence forced a strip sack of Goff, but Tyrone Crawford was unable to come up with the loose ball. The Cowboys never sniffed a turnover.

After the offense woke up with a 75-yard scoring drive, Travis Frederick was flagged for a holding penalty on what would have been Dak Prescott’s game-tying two-point conversion with 7:11 to play. After the Rams were called for holding, the Cowboys’ third chance to tie it up ended when Prescott’s pass to Terrance Williams was slightly deflected and fell to the ground.

After that drive, second-year cornerback Anthony Brown dropped a sure interception that allowed the Rams to kill four more minutes off the clock to set up Greg Zuerlein’s seventh field goal.

The Cowboys’ chances for their second win in eight days ended when Prescott’s fourth-down checkdown to Ezekiel Elliott came up a yard short with 27 seconds to play.

"There was one guy for Zeke to beat when I threw the ball," Prescott said. "I felt like he was going to do it. I guess I can easily say now that I could've extended it and gotten it done, but from my viewpoint I thought that Zeke could make that guy miss and go get it, but we didn't."

There would be no improbable comeback, just a ton of questions for an offense that disappeared in the third quarter and a defense that could not make a play when it mattered and missed Lee.

Making matters worse for the Cowboys is next week’s visitor is the Green Bay Packers, who ended Dallas’ 2016 season last January.